High intensity light emitting diode (“LED”) light sources are used in a variety of applications, including notably, machine vision and related applications. High intensity LEDs are preferred for use in modem day machine vision systems because of their high illumination intensities (e.g., in the range of about 1 to 5 watts per LED), superior radiation characteristics and longer operating lives compared to conventional, low intensity (e.g., 20 to 60 milliwatt) LEDs. However, high intensity LEDs draw substantially higher operating currents, and thus generate substantially more heat during operation, than conventional low intensity LEDs. Consequently, arrangements must be made to conduct heat generated by high intensity LEDs away from the LEDs during operation and to otherwise cool light sources incorporating them. Cooling becomes particularly important in light sources comprised of an array of many, closely spaced, high intensity LEDs due to the cumulative effect of their individual heating.